"She wanted to do something radical, I went for a pixie cut," her hairdresser, Rheanne White, tells Us Weekly exclusively. "I love the idea of taking a look from the 60's and making it new. Lena was my inspiration, she's beyond brilliant."

The 26-year-old HBO Girls star tweeted Saturday, "About to act in my last scene of season 2. Then it's time to lose my voice and do something self destructive vis a vis my hair!"

And it looks like her new boyfriend, Fun. guitarist Jack Antonoff approves of Dunham's new 'do. The couple, who Us first reported were dating last week, attended New York Fashion Week later that same night to see his sister Rachel Antonoff's presentation.

Despite hectic schedules, an insider tells Us, "they have a good time when they can get together!"